Testing for null interface pointer


i know should , simple but....

having following definitions

namespace xyz.dataconversions
{
    public interface iimportablefiletype : iwindowsfiletypedescriptor, ifiletypedescriptor, ioptionsdialogprovider
    {
        void import(ilist<iimportitem> items, importexportresult result = null);
        void import(ilist<string> sourcefilepaths, string destinationfolder, importexportresult result = null);
        void import(string sourcefilepath, string destinationfolder, importexportresult result = null);
    }
}

and this

namespace xyz.dataconversions
{
    public static class abcimports
    {
        public static readonly iimportablefiletype dxf;
        public static readonly iimportablefiletype cmx;
        public static readonly iimportablefiletype hpgl;
    }
}


how test null situation (the following throws exception because hpgl null)

 if (abcimports.hpgl != null)

thanks in advance

i think that there problem. exeception get?

i distilled code in example , works no exception thrown:

void main() { 	 	if (abcimports.dxf != null) 		console.writeline ("not null"); 	else 		console.writeline ("it null"); 	 /* outputs: "it null" */ }  // define other methods , classes here  public interface imyface { 	bool dosomething(); }  public static class abcimports 	 { 		 public static readonly imyface dxf; 		 public static readonly imyface cmx; 		 public static readonly imyface hpgl; 	 }


william wegerson (www.omegacoder.com)




Visual Studio Languages  ,  .NET Framework  >  Visual C#



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